1. Field of the Invention
This invention relates to a recording or reproducing apparatus which draws a tape-like recording medium, such as a magnetic tape or the like, out of a cassette and loads the medium around a head.
2. Description of the Prior Art
A VCR (video cassette recorder) has been used as an apparatus which draws a magnetic tape out of a cassette and loads the tape on magnetic heads. That is, in a VCR, a recording or reproducing operation is performed after performing so-called loading in which a magnetic tape is drawn out of a magnetic tape cassette mounted in the VCR, and the magnetic tape is wound around a drum along the outer circumference of which magnetic heads rotate. After the recording or reproducing operation has been terminated, a so-called unloading operation is performed in which the magnetic tape is taken up around a takeup reel in the magnetic-tape cassette to withdraw the tape from the drum. The loading and unloading operations of the magnetic tape are performed by moving tape guides, usually plural in number, which contact and guide the magnetic tape.
Furthermore, the VCR has the configuration in which the magnetic-tape cassette is mounted on a slide chassis slidably provided on a main chassis of the apparatus. The slide chassis is slid in a direction approaching the drum together with the magnetic-tape cassette during the loading operation, and the slide chassis is slid in a direction away from the drum during the unloading operation.
In such a conventional VCR's configuration, a weak brake is applied to a tape supply reel at the moment of the loading and unloading operations of the magnetic tape. To put it concretely, a weak brake is applied to a supply reel mount which receives the supply reel on the slide chassis for mounting the magnetic-tape cassette. The brake is applied so that the magnetic tape is not drawn out of the supply reel during the loading and unloading operations, and thus the loading position of the magnetic tape does not deviate between immediately before the unloading operation and immediately after the next loading operation. Since it is necessary to draw the tape out of the supply reel when the magnetic tape is not wound around the takeup reel, the brake force is set to a weak value so that a sag is not produced in the tape.
In an apparatus as described above, however, there is the problem that, especially during a takeup operation when unloading, the magnetic tape is drawn out by being taken up around the takeup reel from the supply reel during the takeup operation. As a result, the loading position of the magnetic tape before unloading and the loading position of the magnetic tape in the next loading operation are largely deviated from each other, and the deviation between the front end to start the next recording operation and the rear end of the preceding record becomes large. Hence, discontinuous portions are produced in recorded pictures. Furthermore, the amount of the above-described deviation is not constant due to variations in the brake force, torque and time for the takeup operation. Hence, variations in the amount of deviation are large.